A self-consumption solar kit is a photovoltaic system that is installed in a home or building to generate electricity from solar energy and use it directly in the place where it is produced, instead of sending it to the electricity grid.
This type of photovoltaic installation usually consists of solar panels, a solar inverter and an energy storage system, such as batteries, to be able to use the energy generated during the hours when there is no sun.
The main objective of a self-consumption photovoltaic kit is to reduce dependence on the conventional electricity grid and save on the electricity bill, since using the produced solar energy reduces the kWh/month that must be purchased from the grid.
The implementation of self-consumption systems contributes to the fight against climate change, by reducing the levels of greenhouse gas emissions, while promoting the use of clean and renewable energy.
Types and examples of self-consumption solar kits
There are different types of solar kits that adapt to the needs and characteristics of each installation. Some of the most common types of solar kits are:
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Solar kit for housing: this type of solar kit (insulated or non-insulated) is the most common and is designed to cover the electricity consumption of a home or country house. These self-consumption kits are used to reduce the electricity bill in the case or to provide all the monthly electricity consumption in the case of an isolated home.
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Solar kit for caravan or motorhome: This type of solar kit is designed to power the electrical appliances and electronic equipment of a caravan or motorhome, allowing you to enjoy solar energy anywhere. It includes solar panels, a charge regulator and a battery to store the generated energy.
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Solar kit for pumping water: This type of self-consumption kit is designed for pumping water in rural or isolated areas, where the conventional electrical network does not reach. It includes solar panels, a charge controller and a pump motor.
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Solar kit for public lighting: This type of solar kit is designed for lighting streets and public spaces in isolated or rural areas. It includes solar panels, a battery, a charge controller, and an LED luminaire.
Components of a solar kit
A solar kit can be made up of several elements that work together to generate electricity from solar energy and use it in the installation where the kit has been mounted. These items may include:
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Solar panels: They are responsible for capturing solar energy and transforming it into electrical energy. Solar panels are made up of photovoltaic cells and can be of different sizes and technologies.
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Charge regulator: The charge regulator is the device responsible for protecting batteries from overloads and deep discharges. It also regulates the voltage and current that reaches the batteries to prolong their useful life.
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Inverter: The inverter is the device that converts the electrical energy generated by the solar panels and stored in the batteries into electrical energy usable by the electrical devices found in the installation.
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Batteries: Batteries are devices that allow the energy produced by solar panels to be saved to be used when necessary. They can be of different types such as lead-acid, lithium battery, nickel-cadmium or gel battery.
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Mounting structure: The mounting structure is what holds and holds the solar panels in place. It can be fixed or mobile, depending on the needs of the installation.
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Wiring and accessories: Wiring and accessories are the elements that connect and secure the different components of the solar kit.
These are the basic elements that make up a solar kit, although there may be other optional or additional elements, such as light sensors, monitoring systems, solar tracking systems, etc.
Self-consumption solar kit for isolated housing
A self-consumption solar kit for an isolated home must be designed to cover all the energy needs of the home, since there is no access to the conventional electrical network. Some of the elements that should be considered when selecting a solar kit for an isolated home are:
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Solar panels: Solar panels with an adequate power must be chosen to cover the electrical consumption of the house. In addition, it is important to consider the geographic location and climatic conditions of the area to determine the number of panels needed and their orientation.
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Inverter: The inverter must have adequate capacity to handle the electrical load of the house. It is important to choose an inverter that is compatible with the selected solar panels.
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Batteries: It is essential to include an energy storage system in a solar kit for an isolated house. Batteries must have adequate capacity to store enough energy to cover electrical consumption at night or on cloudy days.
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Charge regulator: The charge regulator is important to protect the batteries from overloads and deep discharges.
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Mounting structure: It is important to select a suitable mounting structure for the solar panels, which is resistant and designed to withstand the climatic conditions of the area.
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Wiring and accessories: Wiring and accessories must be of high quality and suitable for the type of solar kit selected.
How to calculate a self-consumption solar kit?
The calculation of a self-consumption solar kit will depend on the daily electricity consumption of the home and its geographical location. To make a basic calculation, the following steps can be followed:
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Determine the daily electricity consumption: To do this, a list of all electrical appliances and equipment used daily in the home and their consumption in watts (W) must be made. Then, the consumption in W must be multiplied by the hours of daily use of each appliance and electrical equipment, and add the results. The resulting total will be the daily electricity consumption of the home in watt-hours (Wh).
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Choosing solar panels: To calculate the number of solar panels needed, the nominal power of the panel in watts-peak (Wp) and the geographic location of the home must be known. To obtain the amount of energy generated daily by the solar panels, the nominal power of the panel must be multiplied by the number of equivalent hours of sunshine (it can be obtained from an insolation table for the area). Then, the daily electrical consumption of the house in Wh must be divided by the amount of energy generated daily by the solar panels in Wh. The result will be the minimum number of solar panels necessary to cover the daily electricity consumption of the home.
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Choosing batteries: Batteries are necessary to store the energy generated by solar panels and be able to use it at night or on cloudy days. To calculate the capacity of the batteries, the daily electricity consumption of the home in Wh must be multiplied by the number of days of autonomy desired and by the depth of discharge factor (generally 0.5). The result will be the total capacity of the batteries needed in Wh.
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Choosing the inverter and charge regulator: The inverter must have the adequate capacity to handle the electrical load of the house and be in line with the capacity of the selected solar panels. The charge regulator must be compatible with the selected battery system and protect them from overloads and deep discharges.
It is important to note that these calculations are a general guide and there may be other factors to consider based on geographic location, weather conditions, and the specific needs of each home. It is advisable to have the advice of a professional to ensure an accurate calculation and a safe and efficient installation.